JP6796061B2 - How to produce high value-added chemicals from biologically produced materials - Google Patents

Description

The present invention relates to a method for producing high value chemicals such as ethylene, propylene, benzene, butadiene or hydrogen by steam cracking (steam cracking) of paraffinic hydrocarbons.
The present invention relates specifically to methods of producing higher value chemicals from biobased products such as fatty acids or glycerides.

There is an increasing demand for renewable conventional plastics to meet the need for "drop-in appropriately" monomers such as ethylene, propylene, butadiene, aromatic compounds for the production of polymers, and alternative resources such as There is a need for a method for producing high-value basic chemical substances from bio-based products.

However, in order to use biomaterials in steam crackers, it is necessary to meet some technical specifications. That is, since existing steam crackers are designed for hydrocarbon raw materials, additional technical specifications such as boiling point range, metal content, presence of oxygenated compounds, etc. need to be met. Promising biomaterials for steam cracking are fatty acids or triglycerides derived from various sources such as vegetable oils, animal greases, waste cooking oils, algae and the like. These sources are autotrophs such as plants and algae (especially photoautotrophs that use sunlight for growth and fix CO ₂ ) or heterotrophs (heterotrophs) ( It uses reduced carbon for growth and can be produced by, for example, animals, fungi, yeasts, bacteria (divided into phototrophs or organic heterotrophs depending on whether the required energy is obtained from sunlight or reduced carbon). While most heterotrophs use biomaterials (carbohydrates, proteins, fatty acids) for growth, some heterotrophs can use hydrocarbon-based materials as an energy source, for example in the case of methane microorganisms. Uses biological or fossil methane for growth. Heterotrophs, especially methane microorganisms, can convert biomaterials or hydrocarbons to fatty acids or derivatives thereof, such as triglycerides, either in their natural state or after appropriate genetic alterations. The production of fatty acids and their derivatives from CO ₂ , biomaterials or fossil resources by heterotrophs or autotrophs is referred to as "biological production".

Traditional steam crackers basically include a furnace with two sections, a conversion section and a radiant section. Whether the hydrocarbon feedstock enters the conversion section of the furnace, generally in the form of a liquid, or in the form of a vapor in the case of a light feedstock, where it is heated and / or indirect contact with the hot flue gas coming from the radiant section. It is vaporized in direct contact with preheated steam. The vaporized raw material is then introduced into the radiant section where it is cracked to produce a light olefin.
Traditional steam cracking systems are effective in decomposing fairly high quality raw materials such as ethane, liquefied petroleum gas (LPG), naphtha and are also somewhat suitable for gasoline. Atmospheric pressure residues, vacuum gas oil (gasoil, light oil), especially crude oil, contains high molecular weight non-volatile components and components with a tail having a boiling point of more than 550 ° C. Often, these tail components are non-volatile and settle as coke before vaporizing in the conversion section or before entering the radiant section of a conventional pyrolysis furnace. Very low levels (small amounts) of non-volatile material are allowed at the point where the light components completely evaporate (“drypoint”). That is, the initial decomposition in the liquid phase must be minimized to avoid fouling of the conversion section.

The quality of heavy gas oil is very important in steam cracking. The molecular composition, the final boiling point, affects the vaporization capacity (polycyclic aromatic compounds and heavy naphthenes increase fuel oil). A typical technical solution for improving the quality of raw materials is the hydrogenation of heavy gas oils. This can increase the yield of extremely valuable chemicals (HVC). Hydrogenation of aromatic compounds (which may be accompanied by ring-opening of naphthene) significantly reduces tar and increases light olefins. Tar production can also be reduced by distilling the heavy tail of the gas oil.

In general, heavy raw materials are more chemically stable and easier to crack than light naphtha, LPG or ethane, but are more likely to form coke. Since the amount of heat of cracking is small in the heavy raw material, the yield of the light end reaches the maximum at the lower coil outlet temperature (COT). Maximum severity of liquid raw materials means maximizing the yield of light ends, secondary reactions that generally lead to the formation of aromatic compounds begin to increase significantly, and raw material conversion levels are polycyclic aromatic bonds. It is at the point where heavy tar and coke forming spices can be produced. If the coke forming portion is rapidly increased beyond this point, the coil and cooling exchanger will rapidly coke and the operating time will be significantly shortened. On the contrary, if the severity is lowered, the operation time can be lengthened, but the amount of uncracked liquid raw material increases, and the yields of the desired pyrolyzed gasoline and pyrolyzed fuel oil (PFO) deteriorate.

Cracking of heavy hydrocarbons beyond the maximum point of light end yield significantly increases the formation of polynuclear aromatic compounds and causes the coil to caulk rapidly. Since many of the secondary reactions cause coke formation along with the severity of this cracking, it is necessary to shorten the cracking residence time in order to minimize the side reaction. As the hydrocarbon feedstock becomes heavier, the operating window between maximum light ent yield and controllable coke formation narrows.

Generally, the amount of heavy matter (C9 +) produced by steam crackers of naphtha (boiling point in the range of 15 to 200 ° C.) is 6% by weight or less. On the other hand, in the case of normal pressure gas oil, it reaches 8% by weight or more, and in the case of vacuum gas oil, it reaches 20% by weight or more. The production of this heavy material requires reduced coke formation and special attention to the quenching section.

It is necessary to cool the effluent in the radiant section of the steam cracker before separating each cut, and indirect cooling and direct cooling are used, but indirect cooling is preferred in terms of energy recovery (production of high pressure steam). However, in the case of heavy liquid hydrocarbons, which tend to form tar-like molecules, the indirect quenching section is contaminated, resulting in shorter operating time. Tar mist that accompanies the effluent of the furnace adheres to the tubular exchanger at very high temperatures, forming coke-like deposits. Downstream of the tubular cooling system, heavy oil condenses into slugs. Therefore, when the heavy feedstock tends to contain tar-like molecules, the effluent from the furnace is brought into direct contact with cold stable oil to cool and condense the heavy oil as quickly as possible, which is generally direct cooling. The system is used.

As can be seen from the above description, it is understandable that the composition, equipment and optimum operating conditions of steam crackers depend on the composition and boiling range of the fossil raw material and are different from each other. When steam cracking heavy hydrocarbon feedstocks, increase the ratio of steam to hydrocarbons and reduce total pressure to maximize light olefins and minimize coke formation and downstream contamination. , Lower the coil outlet temperature.

That is, the operating conditions of steam cracking are affected by the quality and composition of the raw material mixture, so that even if steam cracking is changed to an alternative raw material, for example, a biologically produced raw material mixture, the operating conditions do not change. Must be done.

[Patent Document 1] (International Publication No. WO2011 / 012438) describes a method for producing a light olefin using a fatty acid as a raw material for steam decomposition of naphtha. Since this feedstock contains certain oxygen (carboxyl units), carbon oxides (CO and CO ₂ ) and short chain water-soluble acids are formed. However, existing steam crackers are not designed to treat these carbon oxides and low pH aqueous products.

[Patent Document 2] (International Publication No. WO2011 / 012439) discloses a method for converting fatty acids and triglycerides into paraffins that can be used in steam cracking called bionaphtha, which does not contain a substantial amount of oxygen. There is. These naphtha paraffins contain 12 to 24 carbons, depending on their origin, and therefore fall within the boiling range of fossil gas oils. This [Patent Document 2] discloses an example in which n-C15 or n-C20 paraffin is steam-cracked instead of fossil naphtha to increase the amount of propylene and ethylene produced. However, there is no mention of the effect of bionaphtha on the operating conditions of steam crackers.

[Patent Document 3] (Chinese Patent No. CN1017237883) discloses a method of mixing liquid hydrocarbon oil and vegetable oil or vegetable fat as raw materials to produce ethylene by steam decomposition.

[Patent Document 4] (International Publication No. WO2014 / 093016) discloses a method for producing ethylene from a naphtha raw material, which pretreats the naphtha raw material before steam cracking.

[Patent Document 5] (US Patent Publication No. US2014 / 0046103) discloses a method for producing naphtha from naturally occurring triglycerides or fatty acids. The obtained naphtha can be used as a raw material for hydrogen decomposition or steam decomposition. Heavy hydrocarbons are hydrocracked to produce short chain hydrocarbons with 4-10 carbon atoms. The purpose of this process is to produce 100% renewable raw gasoline that is free of aromatic hydrocarbons.

[Patent Document 6] (International Publication No. WO2014 / 111598) discloses a method for producing bionaphtha that can be used in a steam cracker. However, there is no description of the operating conditions used in steam crackers, nor is there a description of the effects of mixing.

[Patent Document 7] (European Patent No. EP2290035) also discloses a method for producing bionaphtha, but this document also does not mention the influence of bionaphtha on a steam decomposition apparatus.

[Patent Document 8] (European Patent No. EP2290045) also discloses a method for producing bionaphtha, but there is no teaching regarding the effect on the steam decomposition apparatus.

[Patent Document 9] (European Patent No. EP2917424) discloses a method for hydrogenating vegetable oil and a method for cracking the obtained product with a steam cracker. However, there is no description as to whether or not a mixture of naphtha and bionaphtha can be cracked by simply cracking the obtained bionaphtha.

[Patent Document 10] (US Patent Publication No. US2011 / 03196883) relates to a general method for producing naphtha from a renewable raw material. However, this document also does not teach about the effects of cracking a mixture of normal naphtha and bionaphtha.

[Patent Document 11] (French Patent No. FR2917244) discloses a method for producing paraffin used as bionaphtha by treating vegetable oil. However, there is no teaching on the effect of bionaphtha on the operating conditions of steam crackers.

International Publication No. WO2011 / 012438 International Publication No. WO2011 / 012439 Chinese Patent No. CN101723783 International Publication No. WO2014 / 093016 U.S. Patent Publication No. US2014 / 0046103 International Publication No. WO2014 / 111598 European Patent EP2290035 European Patent EP2290045 European Patent EP2917424 U.S. Patent Publication No. US2011 / 03196883 French Patent No. FR29172424

Therefore, high-value chemicals by steam-decomposing biologically produced materials without changing production facilities that require invested capital or changing the optimum operating conditions for existing naphtha steam-decomposition. There is still a need for a process that can manufacture.

In the first aspect of the present invention, the present invention describes the following (a) to (d):
(A) Prepare an acyclic paraffin stream (A) containing at least 90% by weight of paraffin having at least 12 carbon atoms.
(B) Prepare a hydrocarbon stream (B) containing at least 90% by weight of a component having a boiling point of 15 ° C. to 200 ° C. as measured by ASTM standard D86.
(C) The acyclic paraffin stream (A) and the hydrocarbon stream (B) are mixed to form a feedstock mixture, and the weight content of the acyclic paraffin stream (A) in the feedstock mixture is set to 0. .1% by weight or more, preferably 1% by weight or more, more preferably 5% by weight or more, even more preferably 10% by weight or more, most preferably 20% by weight or more and 70% by weight or less, more preferably 60% by weight or less. Most preferably 50% by weight or less.
(D) Steam cracking of the feedstock mixture at a ratio of 0.2-0.5 kg steam per 1 kg feedstock mixture, preferably containing at least ethylene, propylene and benzene, optionally hydrogen. Obtain cracking products containing toluene, xylene and / or 1,3-butadiene,
A high value chemical, preferably comprising a step, characterized in that step (d) is carried out at a steam / hydrocarbon ratio of 0.5 or less and a coil outlet temperature of at least 820 ° C, preferably at least 830 ° C. Provides a method for producing a chemical containing at least ethylene, propylene and benzene and optionally hydrogen, toluene, xylene and / or 1,3-butadiene.

The steam / hydrocarbon ratio under the above operating conditions is 110% or less of the steam / hydrocarbon ratio of steam cracking when only the hydrocarbon flow (B) is used, and the coil outlet temperature is only for the hydrocarbon flow (B). It is 102% or less of the coil outlet temperature of steam cracking in the case.

The boiling point of acyclic paraffin (a mixture of normal paraffin and isoparaffin) having at least 12 carbon atoms as measured by ASTM standard D86 is in the boiling range of gas oil, i.e. at least 210 ° C, preferably at least 220 ° C. It is generally believed that gas oil cannot be cracked with a naphtha cracker without at least changing operating conditions or equipment design. Since the gas oil has a high final boiling point, it is not completely vaporized at the outlet of the conversion section, and droplets of gas oil are struck on the hot metal surface of the conversion section. As a result, the equipment is rapidly contaminated and caulked.

However, by utilizing the characteristics peculiar to non-cyclic paraffin and mixing non-cyclic paraffin having a boiling range of gas oil with conventional naphtha, it is possible to steam crack with the same equipment without substantially changing the operating conditions. Discovered that quality mixtures can be made, that is, acyclic paraffins are as heavy as gas oils, but can be steam cracked with steam crackers designed for naphtha using typical operating conditions of steam crackers. Was done. In other words, it was discovered that acyclic paraffin (a mixture of normal paraffin and isoparaffin) has at least 12 carbon atoms but has little effect on the operating conditions of steam cracking. Surprisingly, even so, the production of high value chemicals is unaffected and the coil outlet temperature and steam / hydrocarbon ratio are added to the hydrocarbon stream (B) for cracking of the heavy molecule C12. There is no need to match. Therefore, the acyclic paraffin described above can be treated with naphtha, LPG or a mixture thereof, and the equipment, equipment and operating conditions of the steam cracker need not be changed significantly.

In addition, the ethylene and propylene content is increased by increasing the amount of acyclic paraffin flow in the raw material mixture while maintaining the coil outlet temperature and steam / hydrocarbon ratio. This increase in high-value chemicals reduces the formation of unwanted products and cokes, ultimately making the process more efficient.

In addition, the content of acyclic paraffin in the raw material mixture can be reduced to about 0.1% by weight. Therefore, the influence on the operating conditions is extremely low. Also, from the concept of mass balance, the resulting product can be labeled green.

The availability of acyclic paraffins can be an issue when used in large plants that process large amounts of naphtha. In fact, this product is difficult to obtain in large quantities, is less well known and is relatively expensive. However, the content of acyclic paraffin in the raw material mixture may be at least 1% by weight, preferably at least 5% by weight, more preferably at least 10% by weight, and most preferably at least 20% by weight, all of the present invention. It does not deviate from the spirit.

In another embodiment of the present invention, the weight content of linear paraffin derived from the acyclic paraffin stream (A) in the raw material mixture obtained in step (c) is up to 50% by weight, preferably up to 40. By weight%, more preferably up to 30% by weight. It has been discovered that its content in linear paraffin derived from acyclic paraffin stream (A) should not exceed up to 50% by weight. If it exceeds 50% by weight of the maximum content, the cloud point of the mixture becomes too high. As the cloud point rises, pumping problems occur, the storage tanks need to be heated to prevent solidification, and a large investment is required.

In another embodiment of the invention, the acyclic paraffin stream (A) is at least 30% by weight, preferably 50% by weight, more preferably 90% by weight with the stream (a1) containing at least 90% by weight of straight chain paraffin. Obtained by mixing with stream (a2) containing branched chain paraffin. It is preferable to replace a part of the linear paraffin with branched chain paraffin in order to avoid the problem that the cloud point becomes too high due to the content of the linear paraffin being too high.

In an advantageous embodiment of the present invention, branched-chain paraffin is obtained by isomerizing a part of linear paraffin. Preferably, the branched chain paraffin stream (a2) is obtained by isomerizing a portion of the stream (a1) in the same reactor.

Acyclic paraffins are produced by hydrogenation, decarbonylation or decarboxylation of fatty acids and their derivatives (mono-, di- and tri-glycerides, etc.) or fatty acids and their derivatives (mono-, di- and tri). -It is advantageous to produce by simultaneous treatment with naphtha and / or gas oil, which includes hydrogenation of (such as fatty acids).

In another embodiment of the invention, fatty acids and their derivatives (mono-, di- and tri-glycerides, etc.) are mixed with gas oil and then treated with a hydrodesulfurization unit (HDS). By this simultaneous treatment, an acyclic paraffin stream (A) can be obtained in a mixture with gas oil. This is important in that existing HDS units can be used. Further, the gas oil used in this simultaneous treatment may contain sulfur. Therefore, it is not necessary to add additional sulfur compounds to keep the HDS catalyst in a sulfurized state. Therefore, the resulting mixture can be further mixed with a hydrocarbon stream (B) for further steam cracking. In this latter case, existing steam crackers designed to crack naphtha can add value to the gas oil.

In a preferred embodiment of the present invention, the acyclic paraffin stream (A) containing at least 90% by weight of paraffin having at least 12 carbon atoms is a straight chain containing at least 30% by weight of the paraffin having at least 12 carbon atoms. It is characterized in that it contains paraffin and / or at least 20% by weight of maybe branched paraffin, with the rest being single branched paraffin.

In yet another embodiment, the raw material mixture obtained in step (c) is mixed with at least one hydrocarbon stream (B *) prior to step (d). This hydrocarbon stream (B *) is characterized by having an initial boiling point IBP higher than the hydrocarbon stream (B) by at least 2 ° C. and a final boiling point FBP higher than the hydrocarbon stream (B) by at least 5 ° C. The content of the hydrocarbon stream (B *) is preferably 5% by weight, more preferably 10% by weight, still more preferably 20% by weight in the mixture obtained in the step (c). In addition, the steam cracking mixture in step (d) can be obtained by mixing with the acyclic paraffin stream (A) and naphtha (and even heavy products), which still puts the steam cracker device in a steam cracking operating state. It was also discovered that it did not have a significant impact. In this case, the gas oil, which could not be treated by the steam cracker alone, can be upgraded by borrowing the special property of the acyclic paraffin stream (A).

Moreover, the method of the invention can be carried out in the presence of either light or heavy naphtha, without the addition of special equipment. The advantageous advantage of acyclic paraffins obtained in biological production processes is that they can balance the negative effects of using heavy naphtha or gas oils. In this case, the heavy feedstock can be used under operating conditions for producing a certain amount of high value-added chemical substances. Therefore, the present invention hydrogenates and decarbonylates acyclic paraffins, preferably acyclic paraffins obtained in biological production steps (eg, fatty acids and derivatives thereof (such as mono-, di- and tri-glycerides). Produced by simultaneous treatment (including hydrogenation of these) or fatty acids and derivatives (such as mono-, di- and tri-glycerides) with naphtha and / or gas oil (produced by carbonation or decarboxylation). Combined with acyclic paraffin, it provides a versatile process suitable for a wide range from ordinary naphtha to heavier feedstocks such as gas oils or mixtures thereof. The present invention also has the advantage that the steam cracking device does not require major changes. The operating conditions and the type of raw material [content of acyclic paraffin stream (A) with respect to hydrocarbon stream (B)] shall be selected by those skilled in the art by a known method so as to satisfy the production rate required for high value chemical substances. Can be done.

In a preferred embodiment, the ethylene / methane weight ratio of the cracking product produced at the end of the method of the invention (ie, obtained after step (d)) is the ratio obtained when the hydrocarbon stream (B) is steam cracked alone. taller than. This amount of increase is at least 2%, preferably 5%, and most preferably 10%. The ethylene / methane weight ratio when the hydrocarbon stream (B) is steam-cracked alone is 1.7 or less, but when the mixture in step (c) is steam-cracked according to the present invention, the methane yield decreases and the ethylene yield decreases. As a result of the increased rate, the ethylene / methane weight ratio increases. This increase in the ethylene / methane weight ratio provides a technical advantage to the technical bottleneck that was often a problem with many steam crackers. That is, in steam crackers, non-condensed light components (mainly methane and hydrogen) are extracted from the low-pressure section (furnace) to the high-pressure section (fractional distillation), which requires extremely low temperatures and must be combined with the compression section. In many cases, the cold sorting and compression sections were the bottlenecks, so lower methane production in steam cracking equipment can increase the productivity of the entire process. Therefore, the method of the present invention is an alternative to increasing the capacity of the entire process without the need for investment.

From another aspect of the invention, the invention comprises high value chemicals, preferably at least ethylene, propylene, benzene, optionally further hydrogen, toluene, xylene and / or 1,3-butadiene. Provide a manufacturing method for. The method of the present invention includes the following steps (a) to (d):
(A) Prepare an acyclic paraffin stream (A) containing at least 90% by weight of a component having at least 12 carbon atoms.
(B) Prepare a hydrocarbon stream (B) containing a hydrocarbon having 3 to 4 carbon atoms or a mixture thereof.
(C) The acyclic paraffin stream (A) and the hydrocarbon stream (B) are mixed to form a raw material mixture, and the weight content of the acyclic paraffin stream (A) in the raw material mixture is preferably 0. .1% by weight or more and 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less.
(D) The raw material mixture was steam cracked at a ratio of 0.2 to 0.5 kg of steam per 1 kg of the raw material mixture to contain at least ethylene, propylene and benzene, and if necessary, further hydrogen, toluene, xylene and /. Alternatively, a cracking product containing 1,3-butadiene is obtained.
The feature of the present invention is that the steam / hydrocarbon ratio is set to 0.5 or less and the coil outlet temperature is set to at least 820 ° C, preferably 830 ° C in the step (d).

The inventor states that acyclic paraffin can be mixed with light hydrocarbons, propane and butane (LPG), and that it can be easily cracked with a steam cracker without affecting operating conditions. discovered. That is, the steam / hydrocarbon ratio is maintained at 110 or less as compared with the case where only the hydrocarbon flow (B) is steam cracked, and compared with the coil outlet temperature used when only the hydrocarbon flow (B) is steam cracked. The coil outlet temperature can be maintained at 102% or less.

From another aspect of the invention, the invention comprises high value chemicals, preferably at least ethylene, propylene, benzene, optionally further comprising hydrogen, toluene, xylene and / or 1,3-butadiene, a process. Provided is a method for producing a chemical substance. The method of the present invention describes the following (a) to (d):
(A) Prepare an acyclic paraffin stream (A) containing at least 90% by weight of a component having at least 12 carbon atoms.
(B) A hydrocarbon stream (B) containing a hydrocarbon having 3 to 4 carbon atoms or a mixture thereof and a hydrocarbon containing at least 90% by weight of a component having a boiling point in the range of 15 ° C. to 200 ° C. is prepared. ,
(C) The acyclic paraffin stream (A) and the hydrocarbon stream (B) are mixed to form a raw material mixture, and the weight content of the acyclic paraffin stream (A) in the raw material mixture is preferably 0. 1% by weight or more, preferably 1% by weight or more, more preferably 5% by weight or more and preferably 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less.
(D) Steam cracking of the raw material mixture at a ratio of 0.2-0.5 kg of steam per 1 kg of raw material mixture to contain at least ethylene, propylene and benzene, hydrogen, toluene, xylene and / or if necessary. Obtaining a cracking product further containing 1,3-butadiene,
The step (d) is characterized in that the steam / hydrocarbon ratio is 0 or less and the coil outlet temperature is at least 820 ° C, preferably at least 830 ° C.

Under the above operating conditions, the steam / hydrocarbon ratio can be maintained below 110% of the ratio used when steam cracking only the hydrocarbon stream (B), and the coil outlet temperature can be maintained at the hydrocarbon stream (B). ) Can be maintained below 102% of the coil outlet temperature used during steam cracking.
The embodiment other than the above can be a modification of the above embodiment as necessary, and technical advantages can be obtained accordingly.

~ Indicates the method of the invention in which acyclic paraffin is prepared according to various embodiments.

Definition Liquefied petroleum gas (LPG) is basically composed of propane and butane.
Petroleum naphtha or naphtha is defined as a petroleum hydrocarbon fraction having a boiling point of 15 ° C to 200 ° C. It consists of a complex mixture of straight-chain and branched-chain paraffins (single-chain and multi-branched-chain), cyclic paraffins in the range of 5 to about 11 carbon atoms and aromatic compounds.
Light naphtha is composed of C5 to C6 hydrocarbons and has a boiling point range of 15 to 90 ° C., and heavy naphtha is composed of C7 to C11 hydrocarbons and has a boiling point range of 90 to 200 ° C.
Gas oils (light oils) have a boiling point range of about 200-350 ° C., consist of C10-C22 hydrocarbons, and are basically linear and branched paraffins, cyclic paraffins and aromatic compounds (mono-, Includes naphthos and polyaromatics).
The term "acyclic paraffin" means linear paraffin, single-branched paraffin and isoparaffin. It does not include naphthenes and aromatic compounds (unless they are included as traces or impurities).
Hydrogen deoxygenation refers to the reaction of replacing carbon-oxygen bonds with carbon-hydrogen bonds and chemically removing oxygen atoms from the organic molecules that produce water. For example, the following reaction:
_{R-CH 2 -CH 2 -COOH +} 3H 2 -> R-CH 2 -CH 2 -CH 3 + 2H 2 O
Decarbonylation refers to the reaction of chemically removing oxygen atoms from organic molecules as carbon monoxide along with carbon. For example, the following reaction:
_{R-CH 2 -CH 2 -COOH->} R-CH = CH 2 + CO + H 2 O
Decarboxylation refers to the reaction of chemically removing oxygen atoms from organic molecules as carbon dioxide along with carbon. For example, the following reaction:
_{R-CH 2 -CH 2 -COOH->} R-CH 2 -CH 3 + CO 2

It must be understood that the products defined here are not completely pure in most cases. These are generally obtained by distillation, which is not a complete separation technique. In addition, characterization techniques have their detection limits and uncertainties. Therefore, when referring to a product, it should be understood that the product contains at least 98% by weight, preferably 99% by weight, most preferably 99.5% by weight, and the rest of the product is impurities. For example, when referring to LPG, at least 98% by weight of it is propane and butane, but other products ethane and pentane can be included as trace amounts or impurities.

From the first aspect of the invention, the invention comprises high value chemicals, preferably at least ethylene, propylene and benzene, optionally hydrogen, toluene, xylene and / or 1,3-butadiene. Provide a manufacturing method for. This method has the following steps:
(A) Prepare a non-cyclic paraffin flow (A),
(B) Prepare a hydrocarbon flow (B),
(C) The acyclic paraffin stream (A) and the hydrocarbon stream (B) are mixed to form a raw material mixture, and the weight content of the acyclic paraffin stream (A) in the raw material mixture is 0.1% by weight or more. And preferably 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less.
(D) The weight ratio of steam per kg of the raw material mixture is set to 0.2 to 0.5, preferably 0.2 to 0.6 kg, and the raw material mixture is steam-cracked to obtain a high-value chemical substance, preferably. Obtain chemicals containing at least ethylene, propylene and benzene and optionally hydrogen, toluene, xylene and / or 1,3-butadiene.
Including
The step (d) is characterized in that the steam / hydrocarbon ratio is 0.6 or less and the coil outlet temperature is at least 820 ° C, preferably at least 830 ° C.

In step (a), it is advantageous to produce the acyclic paraffin stream (A) from fatty acids or mono-, di- or tri-glycerides by hydrogenation deoxygenation, decarbonylation or decarboxylation.

In another embodiment of the invention, the method of the invention is operated at a coil outlet temperature in the range of 820 to 900 ° C. with a residence time of 0.01 to 1 second.

In a preferred embodiment, the acyclic paraffin stream (A) contains at least 50% by weight, preferably at least 60% by weight, of paraffin having at least 12 carbon atoms relative to the total weight of the acyclic paraffin stream (A). It contains at least 70% by weight, even more preferably at least 80% by weight, even more preferably at least 90% by weight, even more preferably at least 95% by weight, and in particular at least 98% by weight of paraffin having at least 12 carbon atoms. Including%.

The paraffin contained in the acyclic paraffin stream (A) has 12 to 25 carbon atoms, preferably 12 to 20 carbon atoms, more preferably 14 to 18 carbon atoms, and the acyclic paraffin stream. It exists in (A) in the above range.

In the present invention, when preparing an acyclic paraffin stream (A) containing at least 90% by weight of paraffin having at least 12 carbon atoms, the linear paraffin comprises at least 30% by weight and / or the polybranched paraffin. It is preferable to use acyclic paraffin having a weight of 20% by weight or less. More preferably, the linear paraffin is at least 60% by weight and / or the multi-branched paraffin is 15% by weight or less, and more preferably the linear paraffin is at least 80% by weight and / or the multi-branched chain. Paraffin is 10% by weight or less, more preferably linear paraffin is at least 90% by weight, and / or multi-branched chain paraffin is 5% by weight or less. Perhaps branched chain paraffin means paraffin having multiple acyl branched chains having one or more carbons on the base linear paraffin unit.

In a preferred embodiment of the present invention, the hydrocarbon stream (B) contains at least 70% by weight, preferably at least 80% by weight, more preferably at least 90% by weight, most preferably components having a boiling point in the range of 15 ° C. to 200 ° C. Can contain at least 95% by weight. Alternatively, the hydrocarbon stream (B) is at least 70% by weight, preferably at least 80% by weight, more preferably at least 90% by weight, most preferably at least 95% by weight of a hydrocarbon having 3-4 carbon atoms or a mixture thereof. The flow can include% by weight.

In a preferred embodiment of the invention, the hydrocarbon stream (B *) comprises at least 70% by weight, preferably at least 80% by weight, more preferably at least 90% by weight, of components having a boiling point in the range of 17 ° C. to 205 ° C. Most preferably, it can contain at least 95% by weight. Alternatively, the hydrocarbon stream (B *) is at least 70% by weight, preferably at least 80% by weight, more preferably at least 90% by weight, most preferably at least at least a hydrocarbon having 3 to 4 carbon atoms or a mixture thereof. The flow can include 95% by weight.

In a preferred embodiment of the present invention, the decomposition product obtained in step (d) of the method of the present invention may contain one or more of ethylene, propylene, benzene, toluene, xylene, hydrogen or 1,3-butadiene. it can. It is preferable that the decomposition product obtained in the step (d) of the method of the present invention produces as little methane as possible by the thermal decomposition of the fuel oil. In a preferred embodiment of the present invention, the produced ethane is returned to a steam cracking cracking furnace and reused so that basically more ethylene can be obtained.

In particular, the decomposition product obtained in step (d) of the method of the present invention contains ethylene, propylene, benzene and, if necessary, hydrogen, toluene, xylene and 1,3-butadiene. In a preferred embodiment, only a hydrocarbon stream (B) containing at least 90% by weight of a component having a boiling point in the cracking product in the range of 15 ° C to 200 ° C is obtained by steam cracking. It will be higher than the ratio. A typical above-mentioned weight ratio value when steam cracking a hydrocarbon stream (B) containing at least 90% by weight of a component having a boiling point in the range of 15 ° C. to 200 ° C. is 1.7 or less.

In a preferred embodiment of the invention, the raw material mixture can be mixed with steam at a ratio of 0.25 to 0.45 kg of steam per 1 kg of raw material mixture, preferably 0.35 kg of steam per 1 kg of raw material mixture.

In a preferred embodiment of the present invention, the coil outlet temperature can be in the range of 820 to 875 ° C., preferably 820 to 870 ° C., preferably 825 to 860 ° C., and more preferably 835 ° C. to 850 ° C. This coil outlet temperature affects the content of high value chemicals in the decomposition products produced by the method of the invention. For example, the content of benzene in the decomposition product obtained by the method of the present invention is the coil outlet temperature, particularly, steam cracking is operated at a coil outlet temperature in the range of 825 to 860 ° C., more preferably 830 ° to 850 ° C. Can be increased by

In a preferred embodiment of the present invention, the residence time of the raw material in steam cracking can be in the range of 0.05 to 0.5 seconds, preferably 0.1 to 0.4 seconds.

In a preferred embodiment of the present invention, the weight content of the acyclic paraffin stream (A) in the raw material mixture is at least 0.1% by weight, preferably 1% by weight, more preferably 2% by weight, even more preferably 3. By weight%, most preferably 5% by weight, the maximum value being 95% by weight, preferably 90% by weight, more preferably 75% by weight, more preferably 60% by weight, preferably 50% by weight, most preferably 25% by weight. By weight%.

In another embodiment of the invention, the hydrocarbon stream (B) containing at least 90% by weight of a component (or naphtha) having a boiling point in the range of 15 ° C. to 200 ° C. in stroke (b) is 9 or more carbons. It is composed of a mixture of hydrocarbon streams containing hydrocarbons with atoms (C9 +) at various concentrations. The C9 + content can be varied from 0.1% to 15% by weight. The C9 + content can be measured, for example, according to ASTM standard D2425. The content of naphtha in the high C9 + content is at least 1% by weight, preferably 5% by weight, more preferably 10% by weight, even more preferably 15% by weight, most preferably 20% by weight, and the rest from 15 ° C. Other hydrocarbon streams with boiling points in the range of 200 ° C. and low C9 + inclusions. In other words, the hydrocarbon stream (B) is composed of a mixture of at least two naphtha with different properties for surateam cracking and therefore different HVC yields. That is, in the present invention, by adding the acyclic paraffin flow (A), low-quality naphtha (C9 + is 10% by weight) is added to normal-quality naphtha (maximum value of C9 + is 5% by weight) without affecting the operating conditions. It was discovered that it can be blended (containing more than% by weight).

In another embodiment of the invention, acyclic paraffin can be obtained from a fatty acid or its mono, di- or tri-glyceride by its thermochemical treatment.
The term "thermochemical treatment" means hydrogen deoxidation, decarbonylation or decarboxylation of fatty acids or their mono, di- or tri-glycerides, and thus at least 12 carbons. Acyclic paraffins with atoms can be produced by hydrogen deoxidation, decarbonylation or decarboxylation of fatty acids or their mono, di- or tri-glycerides.

Thus, in certain embodiments of the invention, the methods of the invention include the following steps:
(A) Prepare fatty acid or mono-, di- or to-glyceride,
(B) The fatty acid or mono-, di- or tri-glyceride thereof is thermochemically treated to form acyclic paraffin, preferably 90% by weight thereof having at least 12 carbon atoms and described above. Thermochemical treatments include hydrogen deoxidation, decarbonylation or decarboxylation of the fatty acids or their mono, di- or tri-glycerides.
(C) A hydrocarbon stream (B) in which 90% by weight of the component has a boiling point in the range of 15 ° C. to 200 ° C. is prepared and mixed with the acyclic paraffin obtained in the step (b) to prepare a raw material mixture. The weight content of the acyclic paraffin formed and obtained in the step (b) in this raw material mixture is 0.1% by weight or more, preferably 0.1 to 95% by weight, more preferably 1 to 90% by weight. The range, more preferably 2 to 75% by weight, preferably 3 to 50% by weight, most preferably 5 to 25% by weight.
(D) The raw material mixture is steam cracked at a weight ratio of 0.25 to 0.5 kg of steam per 1 kg of the raw material mixture, preferably at a weight ratio of steam per kg of the raw material mixture of 0.35 kg. Obtain cracked and purified products as defined above and / or
Step (d) was carried out at 810, preferably 820 ° C to 875 ° C, preferably 820 to 870 ° C, more preferably 825 to 860 ° C, most preferably 835 ° C to 850 ° C, and 0.05 to 0 at the coil outlet temperature. Performed with a steam / hydrocarbon ratio of 0.6 or less with a residence time of .5 seconds, preferably 0.1-0.4 seconds, and / or
The weight ratio of ethylene / methane in the decomposition product obtained in step (d) is 1.7 or more, and / or
In step (d), the steam / hydrocarbon ratio is 110% or less as compared with the steam / hydrocarbon ratio used for steam cracking using only the hydrocarbon flow (B), and the coil outlet temperature is the hydrocarbon flow (B). ) Only steam cracking is performed so that the temperature is 102% or less of the coil outlet temperature used.

In a preferred embodiment of the invention, the thermochemically treated fatty acid or mono-, di- or tri-glyceride thereof has at least 12 carbon atoms, preferably 12-25 carbon atoms, preferably 12 to 20 carbon atoms. It has 14 to 18 carbon atoms, more preferably 14 to 18 carbon atoms. In a preferred embodiment, at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, preferably at least 80% by weight of the thermochemically treated fatty acid or mono, di- or tri-glyceride thereof. Preferably at least 90% by weight, more preferably at least 95% by weight, has at least 12 carbon atoms. In particular, at least 98% by weight thereof has at least 12 carbon atoms.

In a preferred embodiment of the present invention, a double bond present in the acyl moiety by performing a thermochemical treatment of a fatty acid or a mono, di- or tri-glyceride thereof in the presence of hydrogen, or formed by an element removal reaction. It can be hydrogenated at the same time. Therefore, the final product is paraffinic in nature and can maintain high catalytic activity in the presence of hydrogen.

In a preferred embodiment of the invention, fatty acids can be obtained by physical purification, for example steam distillation or vacuum distillation of fats and oils. In addition, fatty acids can be obtained by hydrolyzing triglycerides of fats and oils, or by acidifying soap. Soap is preferably obtained by saponification of fats and oils or chemical purification of fats and oils, for example, neutralization of free fatty acids present in fats and oils or neutralization of fatty acids obtained by hydrolysis of fats and oils.

Fatty acids or their mono-, di- or tri-glycerides Hydrogen deoxidation, decarbonylation or decarboxylation can be carried out in the presence of hydrogen and at least one catalyst. The catalyst can be a catalytic phase in Ni, Mo, Co or mixtures thereof, such as NiW, NiMo, NiCoW, NiCoMo, NiMoW, CoMoW oxides or sulfides, preferably high surface carbon, alumina, silica, titania, zirconia or mixtures thereof. supported catalyst or high surface area carbon, magnesia, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), calcium silicate (xonotlite), alumina, silica, It can be selected from Group 10 metals (Ni, Pt, Pd) or Group 11 metals (Cu, Ag) supported on silica-alumina or a mixture thereof or an alloy mixture thereof.

Hydrogen deoxidation can be carried out at a temperature of 200 to 500 ° C. and a pressure of 1 MPa to 10 MPa (10 to 100 bar) at a hydrogen / raw material ratio of 100 to 2000 NL / l.

Decarbonylation or decarboxylation can be carried out at a temperature of 100 to 550 ° C. and a pressure of 0.1 MPa to 10 MPa (1 to 100 bar) with a hydrogen / raw material ratio of 0 to 2000 NL / l.

In a preferred embodiment of the present invention, acyclic paraffin can be produced by the following method:
(I') Hydrolyze fats and oils to glycerol and fatty acids to remove glycerol.
(I'') Physical refining of fats and oils (including steam distillation or vacuum distillation),
(I''') Acidification of soap, and (II) Hydrogen deoxygenation, decarbonylation or decarboxylation of fatty acids (this hydrogen deoxygenation, decarbonylation or decarboxylation is hydrogen, preferably high Ni, Co, Mo or mixtures thereof as catalytic phases carried on surface carbon, alumina, silica, titania, zirconia or mixtures thereof, such as NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW, CoMoW oxides or sulfides, or, high surface area carbon, magnesia, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), calcium silicate (xonotlite), alumina, silica, silica - alumina or In the presence of at least one catalyst that can be selected from Group 10 metals (Ni, Pt, Pd), Group 11 metals (Cu, Ag) or alloy mixtures carried on the mixture).

In another preferred embodiment of the invention, acyclic paraffin can be produced by the following method:
(I') Hydrolyze fats and oils to glycerol and fatty acids to remove glycerol.
(I'') Physical refining of fats and oils (including steam distillation or vacuum distillation),
(I''') Soap acidification,
After that,
(II) Decarboxylation of fatty acids (this decarboxylation is a basic oxide dispersed as a bulk material or on a neutral or basic carrier, such as alkaline oxides, alkaline earth oxides, lanthanide oxides, zinc. oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), whether to perform on calcium silicate (xonotlite), alkali or alkaline is obtained by a basic zeolite (exchange or impregnation Earth low silica / alumina zeolite))

In another preferred embodiment of the invention, acyclic paraffin can be produced by the following method:
(I) Hydrolyze fats and oils into glycerol and fatty acids to remove glycerol.
(II) Fractionate fatty acids into a liquid phase and a solid phase containing fatty acids.
(III) Deoxygenate, hydrogen deoxygenate, decarbonylate or decarboxylate a fatty acid (this hydrogen deoxidation, decarbonylation or decarboxylation is carried out in the presence of hydrogen and at least one catalyst. The catalyst preferably contains Co, Ni, Mo and mixtures thereof, NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW, CoMoW oxides and sulfides as catalyst phases supported on high surface carbon, alumina, silica, titania, zirconia. or, high surface area carbon, magnesia, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), calcium silicate (xonotlite), alumina, silica, silica - alumina Alternatively, it can be selected from Group 10 metals (Ni, Pt, Pd), Group 11 metals (Cu, Ag) or alloy mixtures supported on the mixture).

In another preferred embodiment of the invention, acyclic paraffin can be produced by the following method:
(I) Hydrolyze fats and oils into glycerol and fatty acids to remove glycerol.
(II) Fractionate fatty acids into a liquid phase and a solid phase containing fatty acids.
(Llla) Neutralize fatty acids from the solid phase to form soap,
(Lllb) acidifies soap to form fatty acids, and then (IV) decarburizes and carboxylates fatty acids (this decarburized carboxyl is a basic oxide dispersed in bulk form or on a neutral or basic carrier, such as alkali metal oxides, alkaline earth metal oxides, lanthanide oxides, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), calcium silicate (xonotlite) Above, on basic zeolite (eg, alkaline or alkaline earth low silica / alumina zeolite obtained by exchange or impregnation)

As mentioned above, the hydrocarbon stream (B) can include hydrocarbons having 3-4 carbon atoms or mixtures thereof. Therefore, in the second aspect of the present invention, the following steps:
(A) Prepare an acyclic paraffin stream (A) containing at least 90% by weight of a component having at least 12 carbon atoms.
(B) Prepare a flow (B) of a hydrocarbon having 3 to 4 carbon atoms or a mixture thereof.
(C) The acyclic paraffin stream (A) and the above-mentioned hydrocarbon stream (B) are mixed to form a raw material mixture, and the weight content of the acyclic paraffin stream (A) in the raw material mixture is preferably 0. Make it 1% by weight or more
(D) The raw material mixture is steam cracked with steam at a ratio of 0.25 to 0.5 kg of steam per 1 kg of the raw material mixture to obtain a cracking product as defined above.
In step (d), the ratio is 110 or less to the steam / hydrocarbon ratio used for steam cracking only the hydrocarbon stream (B), and steam cracking only the hydrocarbon stream (B). Provided is a method for producing a high-value chemical substance by steam cracking, which comprises setting the coil outlet temperature to 102 or less with respect to the coil outlet temperature used for the production.

In a preferred embodiment of the present invention, the acyclic paraffin of step (a) is produced by hydrogen deoxidation, decarbonylation or decarboxylation of the fatty acid or its mono, di- or tri-glyceride.

In a preferred embodiment of the invention, the acyclic paraffin stream (A) contains at least 50% by weight, preferably at least 60% by weight, preferably at least 70% by weight, more preferably at least 80% by weight of the component having at least 12 carbon atoms. It contains% by weight, more preferably at least 90% by weight, even more preferably at least 95% by weight. In particular, a component having at least 12 carbon atoms is contained in an amount of at least 98% by weight based on the total amount of the acyclic paraffin stream (A).

The paraffin contained in the acyclic paraffin stream (A) has 12 to 25 carbon atoms, preferably 12 to 20 carbon atoms, more preferably 14 to 18 carbon atoms, and is acyclic paraffin. It is preferably present in the stream (A) within the above range.

In a preferred embodiment of the present invention, the decomposition product obtained in step (d) of the method of the present invention further comprises one or more of ethylene, propylene, benzene, hydrogen, toluene, xylene or 1,3-butadiene. You may.

In a preferred embodiment of the present invention, the ethylene / methane weight ratio in the obtained decomposition product is 1.8 or more.

In a preferred embodiment of the invention, the raw material mixture can be mixed with steam at a ratio of 0.25 to 0.451 kg, preferably 0.35 kg of steam per 1 kg of the raw material mixture.

In a preferred embodiment of the present invention, the coil outlet temperature is in the range of 810 to 875 ° C, preferably 820 to 870 ° C, preferably 825 to 860 ° C, more preferably 835 ° C to 850 ° C. This coil outlet temperature affects the content of high value chemicals in the decomposition products produced by the method of the invention. For example, when steam cracking is operated at the coil outlet temperature described above, particularly at a coil outlet temperature in the range of 825 ° C to 860 ° C, preferably 830 ° C to 850 ° C, the content of benzene in the decomposition product obtained by the method of the present invention is contained. The amount increases.

In a preferred embodiment of the present invention, the residence time can be in the range of 0.05 to 0.5 seconds, preferably 0.1 to 0.4 seconds.

In a preferred embodiment of the present invention, the weight content of the acyclic paraffin stream (A) in the raw material mixture is 0.1 to 95% by weight, preferably 1 to 90% by weight, more preferably 2 to 75% by weight, and further. It is preferably in the range of 3 to 50% by weight, most preferably 5 to 25% by weight.

In a preferred embodiment of the invention, acyclic paraffin can be obtained by hydrogen deoxidation, decarbonylation or decarboxylation of fatty acids or mono-, di- or triglycerides thereof.

Chemical component characterization Reagents and product analysis itself are known to those of skill in the art. In particular, the boiling point of the product is measured using ASTM standard D86. Also, the composition of the various streams is characterized by ASTM standard D5443. Additional information can be obtained by well-known PIONA analysis. This PIONA analysis is a standardized gas chromatography technique for determining n-paraffin, i-paraffin, n-olefin, i-olefin, c-olefin, naphthene and aromatics (PIONA). For molecules heavier than C10, the contents of normal paraffin, isoparaffin and naphthenic acid are determined using the method of UOP990. In addition, the complete properties of the mixture are determined in combination with ASTM standard D2425 and GCxGC or LC-GCxGC according to the method described in Journal of Chromatographic Science, Vol. 45, November / December 2007 pages 643-649.

General procedure for steam cracking A steam cracker is a complex industrial facility that can be divided into the three main zones (i) to (iii) below, and each zone has multiple types of equipment with extremely specific functions. doing.
(I) Pyrolysis or cracking furnaces, cooling exchangers, hot zones including quench loops,
(Ii) Decompression gas compressor, purification / separation column, compression zone including dryer,
(Iii) A cold zone containing a cold box, a demethane tower, a cold separation column sorting tower, C ₂ and C ₃ converters, and a gasoline hydrostabilized reactor.
Hydrocarbon cracking is performed directly in a tubular reactor in a heating furnace (furnace). Layouts of coiled tubes of various tube sizes and structures, such as U-tubes or straight tubes, can be used. The diameter of the tube ranges from 1 to 4 inches. Each furnace consists of a conversion zone (waste heat is recovered) and a radiant zone (pyrolysis occurs). The raw material mixture is preheated to about 530-650 ° C. in the conversion zone, or the raw material is preheated in the conversion section and then mixed with diluted steam before flowing into the radiation zone. In the radiation zone, thermal decomposition is performed at the coil outlet temperature of 800 to 900 ° C. described above. The residence time is 0.01 to 1 second, which varies depending on the type of raw material and the desired degree of decomposition. For naphtha steam cracking, the coil outlet temperature is at least 820 ° C and the steam / hydrocarbon ratio is 0.6. On the other hand, in the case of gas oil, it is necessary to increase the steam / hydrocarbon ratio and lower the coil outlet temperature in order to avoid rapid coking. As already mentioned, the residence time in the advantageous embodiment is 0.05 to 0.5 seconds, preferably 0.1 to 0.4 seconds. The weight ratio of the steam / raw material mixture is 0.25 to 0.5 kg / kg, preferably 0.30 to 0.45 kg / kg, preferably 0.35 to 0.4 kg / kg. The severity of the steam cracking furnace can be adjusted by temperature, residence time and hydrocarbon pressure. The coil outlet pressure is 750 to 950 mbar, preferably 800 to 900 mbar, more preferably about 850 mbar. The residence time and temperature of the raw material in the coil must be considered together. The coke formation rate determines the maximum permissible severity. Lowering the operating pressure facilitates the formation of light olefins and reduces the formation of coke. The lowest possible pressures are (i) the outlet pressure of the coil is maintained at atmospheric pressure as much as possible at the suction part of the cracked gas compressor, and (ii) it is diluted with steam to reduce the pressure of hydrocarbons (thus, coke formation rate). Can be substantially slowed down). The steam / raw material mixture weight ratio is maintained at a level sufficient to limit the formation of coke.

In the effluent from the pyrolysis furnace, unreacted raw materials, desired olefins (mainly ethylene and propylene), hydrogen, methane, C ₄ mixture (mainly isobutylene and butadiene), pyrolysis gasoline (fragrances in the range of C _{6 to} C ₈ ) Includes compounds), ethane, propane, diolefins (acetylene, methylacetylene, propadiene) and heavy hydrocarbons (pyrolytic fuel oils) that boil over the temperature range of the fuel oil. The decomposition gas is rapidly cooled to 338-510 ° C. to stop the thermal decomposition reaction, minimize the subsequent reaction, and generate high-pressure steam in the parallel transfer line heat exchanger (TLE) to reduce the sensible heat of the gas. to recover. In a vapor phase raw material based plant, the TLE-quenching gas stream is sent directly to the rapid water cooling tower where the circulating cold water further cools the gas. In a plant based on a liquid phase raw material, the fuel oil fraction is separated from the decomposed gas by condensing with a prefractionator in front of the rapid water cooling tower. In both types of plants, the main part of diluted steam and heavy gasoline in the cracked gas is condensed in a rapid water cooling tower at 35-40 ° C. The water-cooled gas is then compressed to about 25-35 bar in 4 or 5 steps. Condensed water and light gasoline are removed during each compression step. The decomposition gas is washed with a caustic solution or a regenerated amine solution, and further washed with a caustic solution to remove acid gases (CO ₂ , H ₂ S and SO ₂ ). The compressed decomposition gas is dried with a desiccant, cooled to an extremely low temperature with a propylene and ethylene refrigerant, and separated into products (front-end demethane, front-end depropane or front-end deethane).

In the form of front-end demethane, the tail gas (CO, H ₂ and CH ₄ ) is first separated from the C ₂₊ component at about 30 bar in the demethane tower. The bottom product is sent to the deethane column, the top product is treated with an acetylene hydrogenator and further fractionated by a C ₂ split column. Bottom product deethanizer is fed to depropanizer, the overhead product is treated with methyl acetylene / propadiene hydrogenation unit, further, be fractionated by C ₃ resolution column. The bottom product of the depropane tower is sent to the debutane tower where C ₄ is separated from the pyrolysis gasoline distillate. In this separation sequence, H ₂ required for hydrogenation is added to the C ₂ stream and C ₃ stream from the outside. The H ₂ required for this is generally recovered from the tail gas (methaneation of residual CO and further concentration in a pressure swing adsorption unit). The front-end depropaneing configuration commonly used in steam crackers is based on gas sources. In this configuration, after removing the acid gas after the third stage compression step, the lighter components are separated from C ₄₊ to C _{3 in the depropane} column. The top component of this depropane tower is compressed in four stages to about 30-35 bar. The acetylene and / or diene fraction in the C ₃ -cut is catalytically hydrogenated by the H ₂ present therein. Further light gas stream by hydrogenation demethanizer is deethanizing is C ₃ split. The bottom product of the deethanizer may be C ₃ split. In another variant configuration, the C ₃ -top component is first deethanelated, treated with C ₂ as described above, and C ₃ is treated with a C ₃ acetylene / diene hydrogenator and a C ₃ split column. The C ₄ + tower bottom component of the depropane tower is debutaneized to separate C ₄ from the pyrolyzed gasoline.

There are two versions of the front-end deethane separation sequence. The product separation sequence is the same as the front-end demethaneization and the front-end depropane separation sequence is the same as the third stage compression step. First, the gas is deethanelated at about 27 bar to separate C _2- from C ₃₊ . The top C _2- stream is sent to a catalytic hydrogenation unit where the acetylene in this C _2- stream is selectively hydrogenated. The hydrogenated stream is cooled to a very low temperature and demethanesized at a low pressure of about 9-10 bar to remove tail gas. The bottom C ₂ stream is divided into a top ethylene product and a bottom ethane stream for recycling. At the same time, the bottom C ₃ + flow from the front-end deethane column is product-separated in a depropane column, the top product is treated with a methylacetylene / propadiene hydrogenation unit, and a C ₃ split column. Fraction with. The bottom product of the depropane tower is sent to the debutane tower to separate C ₄ from the pyrolysis gasoline distillate.

In a newer version of the front-end deethaneization separation, the decomposition gas is caustically cleaned and precooled after a three-stage compression step and then deethanelated at a top pressure of about 16-18 bar. In the next step, the top current (C _2- ) of the net is further compressed to about 35-37 bar. It is sent to a catalytic transducer to hydrogenate acetylene with the hydrogen remaining in the stream. After this hydrogenation, the flow is cooled and demethanezized to remove tail gas from the C ₂ tower bottom flow. C ₂ is split by a low pressure column operating at a pressure of 9 to 10 bar instead of a 19 to 24 bar high pressure C ₂ splitter, which normally uses propylene refrigerant for reflux condensation of the column. In this low pressure C ₂ splitter separation system, an overhead cooling and compression system is incorporated into the heat pump and open cycle ethylene refrigeration circuit. The ethylene product becomes the purge stream of the ethylene freezing and recirculation system.

The ethane tower bottom of the C ₂ splitter is returned to steam cracking for reuse. Propane may be re-cracked depending on the market price. Recycle steam cracking is performed in two or more dedicated pyrolysis furnaces for continuous operation of the plant even while one of the recirculation furnaces is decoked.

There are many other transformation methods for the above forms. In particular, try to remove unwanted acetylene / diene from ethylene and propylene cuts. Since steam cracking does not have a catalyst, steam cracking does not refer to a catalyst as in FCC (fluidized bed contact decomposition). In catalytic cracking, the hydrocarbon raw material is cracked in the presence of a catalyst.

General Procedures for Thermochemical Treatment of Fatty Acids or Their Mono-, Di-, Tri-Glyde Fatty Acids or their Mono-, Di-, Tri-Glyde are natural fats and oils or biologically produced fatty acids or derivatives thereof (vegetable oils) And animal fats, preferably non-edible highly saturated oils, food wastes, by-products of vegetable oil refining, can be selected from mixtures thereof) or from biomaterials, CO ₂ or hydrogen chemicals Biologically produce fatty acids or their mono, di- and tri-glycerides on-purpose. Fatty acids or mono-, di-, tri-glycerides thereof can be obtained by physically and / or chemically purifying and pretreating natural fats and oils or biologically produced fatty acids or derivatives thereof. Physical purification and alkaline / chemical purification differ primarily in the method of removing free fatty acids. In chemical purification, free fatty acids, mostly phospholipids and other impurities, are removed during neutralization with alkaline solutions, usually NaOH. In physical purification, free fatty acids are removed by distillation during deodorization. Phospholipids and other impurities must be removed prior to steam distillation of fats and oils.

Preferably, the fatty acids or mono-, di-, and tri-glycerides thereof obtained by pretreating natural fats and oils or biologically produced fatty acids or derivatives thereof by physical and / or chemical purification are linearly saturated. It can be heat treated to obtain paraffin. Various methods for converting the fatty acid or its mono-, di-, tri-glyceride into acyclic paraffin used as a raw material for steam cracking of the present invention for producing light olefins, diene and aromatic compounds are described below. The option exists.
(I) Catalytic hydrogen deoxidation,
(Ii) Catalytic decarbonylation or decarboxylation, or (iii) Thermal decarboxylation of fatty acid soaps.

The first option consists of hydrogen deoxidation, which removes oxygen atoms from fats and oils. This can be done for fatty acids or their mono, di and tri-glycerides. This hydrogen deoxidation can be carried out in a continuous fixed bed reactor, a continuous stirring tank reactor or a slurry type reactor. The reactor contains a solid catalyst selected from Ni, Mo, Co and mixtures thereof such as NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW and CoMoW oxides or sulfides, preferably high surface carbon, alumina, silica. , titania or zirconia and mixtures thereof supported on the catalyst, high surface area carbon, magnesia, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite _{(BaTiO 3, ZnTiO 3),} ( xonotlite) , Calcium silicate, alumina, silica or silica-alumina or a mixture thereof is charged with a catalyst of a Group 10 metal (Ni, Pt, Pa) or a Group 11 metal (Cu, Ag) or an alloy mixture thereof. It is preferred that the support of the catalytically active phase be a low acidity, preferably neutral or basic carrier, to avoid hydrogen isomerization reactions and cracking under high temperature and pressure in the presence of hydrogen that produces branched paraffins. The temperature range is 200 to 500 ° C., the pressure is 1 MPa to 10 MPa (10 to 100 bar), and the hydrogen / fatty acid or mono-, di- or tri-glyceride raw material ratio is 100 to 2000 Nm ³ / liquid m ³ . For optimum performance and stable continuous operation, when Mo and / or Co is used, the active metal component of the catalyst is preferably in the form of sulfide.

It is preferable that a trace amount of decomposable sulfur compound is present or that it is intentionally added to the raw material in order to maintain the metal sulfide in a sulfide state. H ₂ S Examples of the sulfur compounds, COS, CS _2, mercaptans (e.g. methyl sulfide), thio - ether (e.g. dimethyl) disulfide (such as dimethyl disulfide), thiophene, tetrahydrothiophene compounds. Multiple reactions occur under hydrogen deoxidation conditions. The simplest reaction is hydrogenation of the double bond in the alkyl chain. The reaction of removing oxygen atoms from the CO bond is a difficult reaction. Both the carboxyl group of the fatty acid and the hydroxyl group of the glycerol unit are hydrogen deoxidized. As a result, linear paraffin is produced from fatty acids, and propane is produced from glycerol. Depending on the conditions (catalyst, temperature, hydrogen column), the carboxyl group can be decomposed to generate CO / CO ₂ (decarbonylation and decarboxylation), which can be further hydrogenated to methane. Hydrogenation of fatty acids or their mono, di- and tri-glycerides can also be carried out in the presence of naphtha and / or gas oils and the latter hydrogenation treatment can be carried out simultaneously. The hydrogenation process consists of hydrodesulfurization, hydrodenitrogenation, hydrodemetallization, and hydrogen dearomatization. These hydrogen deoxidization and hydrogenation treatments consume large amounts of hydrogen.

The second option consists of decarbonylation and decarboxylation of fatty acids or their mono-, di-, tri-glycerides. Fatty acids can be obtained from fats and oils by physical purification (steam distillation / vacuum distillation), by (steam) splitting of triglycerides, or by splitting (acidification) of soaps with acids. Decarbonylation or decarboxylation can be carried out in the presence of a solid catalyst in a batch tank reactor, continuous fixed bed reactor, continuous stirring tank reactor or slurry reactor. The catalyst is preferably Ni, Co, Mo or an alloy mixture thereof as the catalyst phase carried on high surface carbon, alumina, silica, titania or zirconia, such as NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW and CoMoW oxides. or can be selected from among sulfide, or high surface area carbon, magnesia, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), silicate Karushiuwa ( It can be selected from Group 10 metals (Ni, Pt, Pd) and Group 11 metals (Cu, Ag) supported on (zonotrite, etc.), alumina, silica or silica-alumina or a mixture of the latter. The support of the catalytically active phase is preferably low in acidity, preferably neutral or basic, to avoid branched-chain paraffins and hydroisomerization reactions that cause cracking. Decarboxylation can also be performed on basic oxides or basic zeolites (such as alkali metal or alkaline earth metal low silica / alumina zeolites obtained by exchange or impregnation). Alkali metal oxides as the basic oxides, alkaline earth metal oxides, lanthanide oxides, zinc oxide, spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), Examples include calcium silicate (zonotrite, etc.), which may be dispersed on a bulk material or a neutral or basic carrier.

Hydrogen is not required for the decarboxylation reaction, but decarbonylation is preferably carried out in the presence of hydrogen. That is, hydrogen stabilizes the catalytic activity by strongly adsorbing and removing unsaturated species from the catalyst surface by the hydrogen addition reaction (for example, when decarbonylation is the dominant reaction pathway) from the catalyst surface by the hydrogen addition reaction. The presence of hydrogen further hydrogenates the double bonds present in the acyl moiety in the fatty acid, so that a paraffin reaction product can be obtained by decarbonylation or decarboxylation process. Decarbonylation or decarboxylation of fatty acids or their mono-, di-, tri-glycerides can be carried out in the presence of hydrogen at a temperature of 100-550 ° C. and a pressure of 0.01-10 MPa. The hydrogen / raw material ratio can be 0 to 2000 NL / l. It is also preferred to decarbonylate or decarboxylate the fatty acid or its mono-, di-, tri-glyceride in the presence of naphtha and / or gas oil and simultaneously perform the latter hydrogenation treatment. The hydrogenation process consists of hydrodesulfurization, hydrogen denitrification, hydrogen demetallization, and hydrogen dearomaticization.

Thermochemical treatment of the fatty acid or its mono-, di-, tri-glyceride in the presence of hydrogen, preferably as a catalytic phase supported on high surface carbon, alumina, silica, titania, zirconia or a mixture of the latter. Ni, Mo, Co and mixtures thereof, such as NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW and CoMoW oxides or sulfides, or high surface carbon, magnesia, zinc oxide, spinels (Mg ₂ Al ₂ O ₄ , ZnAAl ₂ O ₄ ), perovskite (BaTIO ₃ , ZnTiO ₃ ), calcium silicate (zonotrite, etc.), alumina, silica or silica-alumina and Group 10 metals supported on a mixture of the latter (Ni, Pt, Pd), When performed on a catalyst selected from Group 11 metals (Cu, Ag) or an alloy mixture thereof, various oxygen removal reactions, hydrogen deoxidation, decarbonylation, depending on the type of catalyst and operating conditions. And decarboxylation may occur at the same time.

A third option for obtaining acyclic paraffin is thermal decarboxylation of fatty acid soaps. Soaps are chemically purified by neutralizing fatty acids, producing purified triglycerides and soaps, neutralizing fats and oils obtained after (steam) division of glycerides, direct saponification of glycerides with basic oxides or basic hydroxides, soaps. And can be obtained in the production of glyrol. Decarboxylation has been carried out by decomposing fatty acids in pressurized hot water using alkaline hydroxides, but alkanes and CO ₂ are produced. It has been reported since 1947 that the calcium soap of tung oil is decomposed by distillation. Preferred soaps consist of alkali, alkaline earth metals, lanthanides, zinc or aluminum cations. Thermal decarboxylation of the soap can be carried out by heating the molten soap until it decomposes into the corresponding paraffin or olefin and the corresponding metal carbonate or metal oxide / hydroxide and CO ₂ . The thermal decomposition of this soap is preferably carried out in the presence of liquid, supercritical or vaporized water.

In certain embodiments of the invention, acyclic paraffin can be obtained from pretreated solid fatty acids.
[Fig. 1a] to [Fig. 1b] show an embodiment in which a fatty acid is separated into a liquid fraction and a solid fraction. Fractionation, or "dry winterization," is a solid that uses a separation method that involves controlled crystallization and the use of solvents or dry treatment (also called dewaxing). It is a removal operation. This separates petroleum fractions by the difference in melting point. This separation process has two main stages, the first of which is crystallization. Crystals grow when the temperature of the melted fat or oil or its solution is lowered. The fatty acid composition of the crystal and mother liquor on which the solubility at its final or separation temperature is formed is determined. The second step of sorting is the separation process. There are several options, including vacuum filters, centrifuges, conical screen-scroll centrifuges, hydraulic presses, membrane filter presses, decanters, etc., each with its own advantages and disadvantages. Sorting can also be done naturally during storage or transportation, which is the basis of the dry sorting process. This process is the oldest type of process and is competitive in terms of product quality over other expensive processes such as solvent and detergent separation as the separation method is steadily improving. Fractionation can also be carried out in the presence of solvents such as paraffin, alkyl acetates, ethers, ketones, alcohols or chlorinated hydrocarbons. The use of solvents promotes crystallization and allows many materials to crystallize before the slurry becomes unmanageable. The term "fractional crystallization" is used herein to include "dry winterization,""dryfractionation," and "solvent fractionation."

The solid fatty acid obtained by the fractionation treatment can be converted to acyclic paraffin by hydrogen deoxidation, decarbonylation or catalytic decarboxylation (FIG. 1a) or thermal decarboxylation of fatty acid soap (FIG. 1b). Hydrogen deoxygenation, decarbonylation, decarboxylation and thermal decarboxylation have been described above.

FIG. 1a shows a specific embodiment of the method of the present invention for carrying out sorting. The fat and oil 26 is hydrolyzed to recover the glycerol 27 and the fatty acid mixture 28. The fatty acid mixture 28 is fractionally crystallization and fractionated 21 to separate the solid phase 22 and the liquid phase 23. The solid phase 22 is sent to the hydrogen deoxidized section 30 or the decarbonylated / decarboxylated section 31 where it is converted to acyclic paraffins 35, 36. The acyclic paraffin is blended with fossil LPG, naphtha or gas oil 40 and the resulting blend is steam cracked 50. Steam-cracked products are cooled, compressed, fractionated and refined 51. The liquid phase 23 obtained from the fractional crystallization is sent to the biodiesel production section 25.

In another embodiment (FIG. 1b), the fat 126 is hydrolyzed to recover the glycerol 127 and the fatty acid mixture 128. The fatty acid mixture 128 is fractionally crystallization 121 to obtain fractions of solid phase 122 and liquid phase 123. Soap 131 is produced by neutralizing the free fatty acids of the solid phase 122. This soap is sent to the decarboxylation section to convert acyclic paraffin 135 to metal carbonate or C0 ₂ 136. The acyclic paraffin 141 is blended with fossil LPG, naphtha and gas oil 140, and the blend is steam cracked 150. The liquid phase 123 obtained from the fractional crystallization is sent to the biodiesel production section 25.

In the embodiment shown in FIG. 1c, the fats and oils are physically purified by vacuum distillation or steam distillation 210 to recover the mixed fatty acid 212 (top product) and the triglyceride 211 (bottom product). As an option, the fat and oil 221 is hydrolyzed to produce mixed fatty acid 222 and glycerol 223. To improve the quality of the mixed fatty acids, the double bonds of the acyl moiety can be hydrogenated, or the fats and oils can be hydrogenated before hydrolysis to remove the residual double bonds and sent to the hydrolysis step 221. it can. The mixed fatty acids are sent to the hydrogen deoxidizing section 230 where they are converted to acyclic paraffin 236 or to the degalbonylation / decarboxylation section 231 where they are converted to acyclic paraffin 235. Acyclic paraffin 241 is blended with fossil LPG, naphtha, gas oil 240 and steam cracked 250. The steam cracked product is cooled, fractionated, compressed and refined 251.

[Fig. 1d] shows the method of another specific embodiment of the present invention, in which fats and oils are physically purified by vacuum distillation or steam distillation 310 to recover mixed fatty acid 312 as a tower top product and triglyceride as a bottom product. Collect 311. Both fats and oils, which may contain free fatty acids 321 or physically purified triglycerides 320, are sent to the hydrogen deoxidized section for conversion to acyclic paraffin 335 and biopropane 330. The acyclic paraffin 341 and biopropane 343 are blended with fossil LPG, naphtha and gas oil 340 and sent to a steam cracker 350. The steam-cracked product is cooled, fractionated, compressed and refined 351.

In yet another embodiment (FIG. 1e), the fat is saponified 521 to recover soap 522 and glycerol 523. As an option, fats and oils can be hydrolyzed to produce mixed fatty acids and glycerin. Alternatively, soap 525 can also be obtained during the neutralization step during the chemical refining step of the raw material fat 524. As another source, soap 530 can also be obtained with fatty acid neutralization 529 obtained by (steam) splitting of fats and oils 526 to obtain fatty acids 528 and glycerol 527. The fats and oils are hydrogenated to remove residual double bonds before being sent to the saponification process 521 or the hydrolysis process 526. Soap is sent to decarboxylation section 531 to convert acyclic paraffin 535 to metal carbonate or CO ₂ 536. Acyclic paraffin 541 is blended with fossil LPG, naphtha, gas oil 540 and steam cracked 550. The steam-cracked product is cooled, compressed, sorted and purified 551.

FIG. 1f shows yet another specific embodiment of the present invention. The fats and oils are physically and / or chemically purified (see each figure above) to recover the mixed fatty acids and the mono, di- or tri-glyceride 610 as products. These fatty acids, mono-, di- or tri-glycerides and any mixture thereof 621 are sent to a common thermochemical treatment section with fossil naphtha and / or gas oil fraction 620, where hydrogenation, hydrogenation. It is deoxidized, decarbonylated and / or decarboxylated to substantially convert to acyclic paraffin 631 and biopropane 630. In this case, the fossil naphtha and / or gas oil fraction is simultaneously hydrotreated [including hydrodesulfurisation, hydrodearomatisation and / or hydrodemetalisation]. .. A blend of the resulting substantially acyclic paraffin with the hydrogenated fossil naphtha and / or gas oil 641 (which may also contain biopropane 643) is blended with fossil LPG, naphtha, gas oil 640. , Sent to steam cracker 650. The steam-cracked product is cooled, compressed and refined 651.

The products obtained according to the methods shown in FIGS. 1a to 1f or any combination thereof contain light olefins (ethylene, propylene, butene), dienes (butadiene, isoprene, (di) cyclopentadiene) as main components. And piperylene), including aromatic compounds (benzene, xylene mixed with toluene). In addition, methane, ethane and propane can also be obtained.

Example 1
SPYRO Simulation Steam cracking of naphtha, linear saturated paraffin, saturated isoparaffin or branched chain saturated paraffin and a mixture of naphtha and acyclic paraffin was evaluated with SPYRO software and the product distribution was simulated. Reference naphtha was also evaluated. The results of PIONA analysis of this naphtha (referred to as naphtha 1) are shown in [Table 1].

The operating conditions and the results of the products obtained by steam cracking pure naphtha 1, pure n-C15, iso C15 and various mixtures of naphtha 1 and n-C15 are shown in [Table 2].

Iso C15 is a mixture of multi-branched acyclic paraffins with 15 carbons. As can be seen from [Table 2], in the SPYRO simulation, steam cracking of acyclic linear paraffin (nC15) produces one having a higher ethylene content than naphtha or steam cracked multi-branched-chain isoparaffin. Moreover, the total amount of all high value chemicals (ethylene, propylene, butadiene, benzene and hydrogen) is substantially higher than in the case of linear paraffin. Linear paraffin produces less methane and C9 + components. According to the SPYRO simulation, the mixture of naphtha and acyclic linear paraffin has a higher ethylene and propylene content than the case of naphtha 1 alone. The HVC yield and final HVC (ultimate HVC) (assumed to be 80% yield in ethylene after recirculating ethane in the furnace) for all blends are higher than for naphtha 1 alone. The ethylene / methane ratio for all blends is higher than for naphtha, here 1.7. Furthermore, the C9 + component of each blend does not increase. The thermal duty of the irradiated section per HVC unit is lower than that of blending with linear paraffin, which is 12 carbons or more.

Examples 2 and 3
Pilot steam crackers were tested using various raw material mixtures (naphtha only, 50/50 weight mixture of naphtha and thermochemically treated coconut oil or jatrofa oil). The composition of crude palm oil and crude jatropha oil used in this test is shown in the table below.

Hydrodeoxygenation of palm oil uses a pre-sulfurized commercially available CoMo catalyst, hydrogen / oil at a liquid space velocity of 1.5 hours- ¹ at a temperature of about 338 ° C and under a pressure of 4 MPa. The ratio was 1500 NL / l. The obtained hydrodeoxygenated palm oil was mainly composed of n-C14 to n-C18 and contained about 100 to 600 ppm by weight of oxygen.
For hydrogenation and deoxidation of jatropha oil, a pre-sulfurized commercially available NiMo catalyst is doped with 1000 ppm by weight of sulfur (as DMDS) at a temperature of 300-360 ° C. for 1.85 hours- ¹ liquid space velocity. The hydrogenation / jatropha oil ratio = 1050 NL / l under a pressure of 6 MPa. Residual oxygen in the product is always 300 ppm by weight or less and basically contains C15-C18 linear paraffin.
Steam cracking was performed at a pressure of 850 mbar, a water / hydrocarbon weight ratio of 0.4, and a residence time of about 0.25 seconds. Example 2 is according to the present invention, in which a 50/50 weight mixture of naphtha and thermochemically treated palm oil is steam cracked. Example 3 is a steam cracking of a 30/70 weight blend of thermochemically treated jatropha oil and typical naphtha (naphtha 3). The PIONA analysis values of naphtha 3 are shown in [Table 3].

In Examples 2 and 3 of [Table 4], ethylene, 1,3-butadiene or ethane was obtained when a mixture of substantially acyclic paraffin and naphtha was steam-cracked instead of steam-cracking naphtha alone. It shows that the amount of paraffin increases and the amount of methane decreases. The total yield of HVC and the final HVC are significantly improved, and the ethylene / methane ratio is always higher than the ratio obtained with fossil naphtha.

Example 4
In this Example 4, the addition of acyclic paraffin to a given naphtha, such as naphtha 1 (whose composition is shown in [Table 1]), unexpectedly results in low quality naphtha, such as naphtha 2 (its composition). (See Table 5) or indicate that there is room to add heavy gas oil fractions, that is, steam cracking of such naphtha can produce higher amounts of HVC. In other words, the addition of acyclic paraffin can increase the value of low-quality naphtha in combination with other high-quality naphtha while maintaining constant operating conditions and constant HVC production. it can.

Naphtha 2 contains 17% by weight of C9 +, as can be seen from [Table 5]. On the other hand, naphtha 1 contains only 3.3% by weight of C9 +. Therefore, naphtha 2 has a higher content of heavy compounds than naphtha 1. When naphtha 2 is steam cracked under the same operating conditions, the production of ethylene and propylene is lower than that of naphtha 1. In addition, the amount of C9 + heavy products during steam cracking increases, increasing the thermal duty per unit HVC. Naphtha 2 is inferior in quality to naphtha 1 and is therefore inexpensive on the market.
In the present invention, as can be seen from [Table 6], a part of high quality naphtha 1 is replaced with low quality naphtha 2 by using acyclic and substantially linear paraffin having 12 or more carbon atoms. Can be replaced with, which does not substantially increase the amount of methane or C9 + heavys produced. In addition, the ethylene / methane ratio is higher than that of naphtha 1 alone, and the thermal duty per unit HVC is lower than that required for naphtha 1 alone.

Therefore, the present invention can further mix normally acyclic, substantially linear paraffins with naphtha, and by adding low quality naphtha, while maintaining the performance of steam crackers, or by adding steam. It is possible to improve the performance of crackers and at the same time provide steam cracking raw materials. In addition, the performance of the steam cracker can be improved while improving the HVC content. Similar results would be obtained if naphtha 2 was replaced with gas oil.
In this example, thermochemical treatment is performed to remove almost all oxygen atoms, basically linear paraffin having 12 or less carbon atoms is blended with fossil naphtha, and the blend is blended with fossil naphtha alone. By steam cracking under the typical conditions used in cases, technical solutions have been discovered for producing high value chemicals from biologically produced fatty acids, mono, di or triglycerides. It shows that it was. Under naphtha cracking conditions, heavy substances (C9 +) are not excessively produced, and the ethylene / methane ratio is higher than that of fossil naphtha alone on the alumina binder.

Example 5
Mixture of naphtha and bio raw material The palm oil of Example 3 (hereinafter referred to as non-isomerized bio raw material) is isomerized by hydrogenation deoxidation to obtain an "isomerized bio raw material". This isomerization was performed using a platinum / SAPO-11 catalyst using an alumina binder, using a vertical downflow plug flow reactor at a temperature of 355 ° C. and under a pressure of 4.0 MPa, H2 / HC ratio = 2000 NL / L, It was carried out at WHSV = 0.5h ^-1 . Gas was removed from the liquid at the outlet of the unit. The main properties of the isomerization product are shown in [Table 7] below.

The cloud point of palm oil after hydrogenation and deoxidation of Example 3 was 17 ° C. as measured according to ASTM standard D7571. It was mixed with light naphtha having a density of 0.6527 g / mL at 15 ° C. at various concentrations. The palm oil of Example 3 was also mixed with the same light naphtha at various concentrations. The cloud point values of the obtained various mixtures are shown in [Table 8] below.

When using non-isomerized biomaterials with a content of 50% by weight in light naphtha, the cloud point of the mixture is -6 ° C, which means that the plant can be planted without the investment of heating the storage or pipe transport equipment. The maximum value that can be used.
The terms and descriptions used herein are provided as examples and are not intended to limit the invention. It can be understood that those skilled in the art can make various modifications within the spirit of the invention and the claims and their equivalents. All terms should be understood in their broadest sense, unless otherwise noted. Therefore, other changes and improvements can be made by reading and understanding the above description. In particular, the dimensions, materials and other parameters described above can be varied according to the needs of the application.

Claims (30)

The following steps (a) to (d):
(A) At least 90% by weight of at least 12 pieces obtained by mixing a flow (a1) containing at least 90% by weight of linear paraffin and a flow (a2) containing at least 30% by weight of branched chain paraffin . An acyclic paraffin stream (A) made of paraffin having a carbon atom is prepared.
(B) Prepare a hydrocarbon stream (B) containing at least 90% by weight of a component having a boiling point in the range of 15 ° C. to 200 ° C. as measured by ASTM standard D86.
(C) The acyclic paraffin stream (A) and the hydrocarbon stream (B) are mixed to form a raw material mixture, and the weight content of the acyclic paraffin stream (A) in the raw material mixture is at least 0. 1% by weight or more and 75% by weight or less
(D) The amount of steam per 1 kg of the raw material mixture is set to 0.2 to 0.5 kg, and the above raw material mixture is steam-cracked to obtain a cracking product.
A method of producing a chemical by steam cracking, which comprises a high value chemical and, in some cases, further containing hydrogen, toluene, xylene and / or 1,3-butadiene.
A method characterized in that step (d) is carried out with a steam / hydrocarbon ratio of 0.6 or less and a coil outlet temperature of at least 820 ° C. The method of claim 1, wherein the flow (a2) comprises at least 90% by weight branched chain paraffin . The method according to claim 1 or 2, wherein a branched chain paraffin stream (a2) is obtained by isomerizing a part of the linear paraffin stream (a1) . The method according to any one of claims 1 to 3, wherein the steam / hydrocarbon ratio in the step (d) is 0.5 or less and the coil outlet temperature is at least 830 ° C. The weight content of the acyclic paraffin stream (A) in the raw material mixture of the above (c) is 1% by weight or more and 50% by weight or less, and / or.
The amount of steam per 1 kg of the raw material mixture of the above (d) is set to 0.2 to 0.6 kg, and the raw material mixture is steam-cracked to obtain a cracking product, and / or.
The cracking product of (d) above contains at least ethylene, propylene and benzene, optionally hydrogen, toluene, xylene and 1,3-butadiene, and / or
The above high value chemicals include at least ethylene, propylene, benzene and, in some cases, hydrogen, toluene, xylene and / or 1,3-butadiene.
The method according to any one of claims 1 to 4 . The item according to any one of claims 1 to 5 , wherein the weight content of the linear paraffin derived from the acyclic paraffin flow (A) in the raw material mixture obtained in the step (c) is 50% by weight at the maximum. the method of. The method according to claim 6 , wherein the weight content of the linear paraffin derived from the acyclic paraffin stream (A) in the raw material mixture obtained in the step (c) is 30% by weight at the maximum. The raw material mixture obtained in the above step (c) is further mixed with at least one kind of hydrocarbon stream (B *) before the step (d), and this hydrocarbon stream (B *) is the hydrocarbon stream (B). The method according to any one of claims 1 to 7 , which has an initial boiling point IBP which is at least 2 ° C. higher than that of the hydrocarbon stream (B) and a final boiling point FBP which is at least 5 ° C. higher than the hydrocarbon stream (B). Claims 1-8 , wherein the acyclic paraffin stream (A) comprises at least 30% by weight linear paraffin and / or 20% or less maybe branched chain paraffin and the rest of the composition is single branched chain paraffin. The method according to any one item. The method according to any one of claims 1 to 9 , wherein the coil outlet temperature is in the range of 825 to 860 ° C. The method according to claim 10 , wherein the coil outlet temperature is in the range of 835 ° C to 850 ° C. The method according to any one of claims 1 to 11 , wherein the residence time is in the range of 0.05 to 0.5 seconds. The method according to claim 12 , wherein the residence time is in the range of 0.1 to 0.4 seconds. The method according to any one of claims 1 to 13 , wherein the weight content of the acyclic paraffin stream (A) in the raw material mixture is at least 1% by weight and 70% by weight or less. The method according to claim 14 , wherein the weight content of the acyclic paraffin stream (A) in the raw material mixture is 15% by weight or more and 55% by weight or less. The method according to any one of claims 1 to 15 , wherein the raw material mixture and steam are mixed at a ratio of 0.35 to 0.45 kg of steam per 1 kg of the raw material mixture. 16. The method of claim 16 , wherein the raw material mixture and steam are mixed at a ratio of 0.40 kg steam per 1 kg raw material mixture. The acyclic paraffin is obtained by catalytic hydrogen deoxidation, catalytic decarbonylation or decarboxylation of a fatty acid having at least 12 carbon atoms or a mono, di- or tri-glyceride thereof, or thermal decarboxylation of a fatty acid soap. The method according to any one of claims 1 to 17 , obtained by carboxylation. 18. The method of claim 18 , wherein the catalytic hydrogen deoxidation, catalytic decarbonylation or decarboxylation is carried out in the presence of other hydrocarbons. 19. The method of claim 19 , wherein the other hydrocarbon is a hydrocarbon having a boiling point in the range of 15 ° C. to 350 ° C. as measured according to ASTM Standard D86. Catalytic hydrogen deoxidation or catalytic decarbonylation or decarboxylation of the above fatty acids or their mono, di- or tri-glycerides is at least one selected from hydrogen and Ni, Mo, Co and mixtures thereof. The method according to any one of claims 18 to 20 , which is carried out in the presence of the catalyst of. 21. The method of claim 21 , wherein the catalyst is selected from NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW and CoMoW oxides or sulfides. The method according to claim 20 or 21 , wherein the catalyst is a catalyst supported on high surface area carbon, alumina, silica, titania or zirconia. The above non-cyclic paraffin is used in the following (1) and (2):
(1) Hydrolyze fats and oils to obtain glycerol and fatty acids, and then remove glycerol, or physically purify the fats and oils by steam distillation or vacuum distillation, or acidify soap to make fatty acids.
(2) Catalytic hydrogen deoxidation, catalytic decarbonylation or decarboxylation of the obtained fatty acid.
Manufactured by the above catalytic hydrogen deoxidation, catalytic decarbonylation or decarboxylation of hydrogen and Ni, Mo, Co and mixtures thereof or high surface carbon, magnesia, zinc oxide, spinel (Mg ₂ Al ₂ O _4). , ZnAl ₂ O ₄ ), perovskite (BaTIO ₃ , ZnTiO ₃ ), calcium silicate, zonotrite, alumina, silica or silica-alumina or a mixture of the latter, Group 10 (Ni, Pt and Pd) and Group 11 In the presence of at least one catalyst selected from among (Cu and Ag) metals or alloy mixtures thereof.
The method according to any one of claims 18 to 23 . 24. The method of claim 24 , wherein the catalyst is selected from NiW, NiMo, CoMo, NiCoW, NiCoMo, NiMoW and CoMoW oxides or sulfides. 25. The method of claim 25 , wherein the catalyst is a catalyst supported on high surface area carbon, alumina, silica, titania or zirconia or a mixture thereof. The method according to claim 18 , wherein acyclic paraffin is produced by thermal decarboxylation of fatty acid soap, and this thermal decarboxylation is performed on the following (i) or (ii).
(I) bulk or neutral or basic supports basic oxide supported on spinel _{(Mg 2 Al 2 O 4,} ZnAl 2 O 4), perovskite (BaTiO _3, ZnTiO _3), calcium silicate, xonotlite,
(Ii) Basic zeolite. The method according to claim 27 , wherein the basic oxide is an alkaline oxide, an alkaline earth oxide, a lanthanide oxide, or a zinc oxide. 27. The method of claim 27 , wherein the basic zeolite is a low silica / alumina zeolite obtained by exchanging or impregnating an alkali metal or alkaline earth. The catalytic hydrogen deoxidation is carried out at a temperature of 200 to 500 ° C. under a pressure of 1 MPa to 10 MPa (10 to 100 bar) and a hydrogen / raw material ratio of 100 to 2000 NL / l.
The above catalytic decarbonylation or decarboxylation is carried out at a temperature of 100 to 550 ° C. under a pressure of 0.1 MPa to 10 MPa (1 to 100 bar) and a hydrogen / raw material ratio of 0 to 2000 NL / l.
The method according to any one of claims 18 to 26 .

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